Endosymbiotic bacteria in insects: guardians of the immune system?

Ioannis Eleftherianos,Julia Accetta,Julio C Castillo,Jaishri Atri

doi:10.3389/fphys.2013.00046

Abstract

Insects have evolved obligate, mutualistic interactions with bacteria without further transmission to other eukaryotic organisms. Such long-term obligate partnerships between insects and bacteria have a profound effect on various physiological functions of the host. Here we provide an overview of the effects of endosymbiotic bacteria on the insect immune system as well as on the immune response of insects to pathogenic infections. Potential mechanisms through which endosymbionts can affect the ability of their host to resist an infection are discussed in the light of recent findings. We finally point out unresolved questions for future research and speculate how the current knowledge can be employed to design and implement measures for the effective control of agricultural insect pests and vectors of diseases.

Highlights

Insects comprise about 95% of all known animal species and are considered one of the most successful groups of living organisms on earth
Previous and recent studies have started to determine the phenotypic response of various insects carrying endosymbionts to infection by bacterial and viral pathogens as well as parasites
These studies have substantially improved our understanding of the complex interactions between insects, their endosymbiotic bacteria and pathogenic organisms in the infection and host immunity processes

Summary

INTRODUCTION

Insects comprise about 95% of all known animal species and are considered one of the most successful groups of living organisms on earth They possess an extremely efficient immune system that allows them to deal with pathogenic infections. Apart from the native microbiota, insects carry symbiotic bacteria that occupy specific cells and tissues within the host These symbiotic microbes live under the pressure of an active immune system and they must devise strategies that allow them to withstand the adverse effects of host immune defense mechanisms (Gross et al, 2009; Douglas, 2011; Weiss and Aksoy, 2011). The results of these studies are of particular interest for developing alternative strategies to transgenic approaches for the efficient management of noxious insects

Endosymbionts and insect immunity

ENDOSYMBIONTS AND THE INSECT IMMUNE RESPONSE TO PATHOGENS

CONCLUSIONS AND FUTURE PROSPECTS

Findings

Drosophila Jun mediates